Every skill in this game is prone to it, but some less than others.
The ones most prone are ones like you said that dont require you to do anything.
Hunting skill is one of the skills I can say would be least prone to macroing. It requires so much stuff (currently hunting cant level). More ideas like hunting into the game will help stop macroing.
But really to stop macroing IMO is just promote active play. If you reward players for playing much more than someone can get macroing, no one will care if someone is macroing. I know I wouldnt care if I got 10x faster gains while active than macroing. People could macro for all I care at that point. Problem is right now many skills its better to macro. I mean look at making bricks. OMG I would die in real life if I did that skill.
No, see above, also Jadzia has an idea where you have to do missions sometimes to keep increasing your skills.
Ya, this isnt a great option. It might be an option if you put it in, but dont force people to do it. Some people dont want to do PVE at all. It would be as bad as forcing people to do PVP to get skills as a crafter or a PVEer.
I think this is a great idea, but I dont want to see leveling up only through these "missions" or "quests" if its here and there sure. But I dont want to do missions all the time to level my skills up either.
I think there should be a break point, where you need to do a quest to keep going. Maybe like once every 10 or 25 points.
They dont even have to be hard missions either.